[Paper] Selected as a PRB Editors' Suggestion

Our work on the magnetic dynamics of vortex clusters in the superconductor CaSb$_2$ has been selected as an Editors' Suggestion in Physical Review B.

When a magnetic field penetrates a superconductor, magnetic flux enters in the form of tiny bundles known as superconducting vortices. While vortices typically repel one another, under certain conditions they can gather into dense clusters. In this work, we use scanning SQUID microscopy to simultaneously image magnetic flux and local magnetic response, enabling us to visualize dynamics within these vortex clusters.

We find that, although the static magnetic flux is relatively uniform within the clusters, vortex motion is strongly suppressed in the interior while a much stronger response appears near the cluster boundaries. This spatially inhomogeneous dynamics is hidden from conventional static magnetic imaging and provides a new way to probe the interactions that hold vortices together.

Our results reveal the unusual behavior of vortex clusters in the weakly type-II superconductor CaSb$_2$ and establish local magnetic-response imaging as a new approach to investigating non-monotonic vortex interactions and the mechanisms underlying unusual vortex clustering.

Publication:
Y. Iguchi, N. Nandi, and M. Oudah
Visualizing Vortex Cluster Dynamics in the Weakly Type-II Superconductor CaSb$_2$
Physical Review B (Letter) 114, L140504 (2026), Editors' Suggestion
DOI: ⁠10.1103/gj5m-ntpz